Method and apparatus for hackling bast fibre stalks



July 21, 1964' c. BOK 3,141,198

METHOD AND APPARATUS FOR HACKLING BAST FIBRE STALKS Filed Feb. 10, 1961 2 Sheets-Sheet 1 INVENTOR. CORNELI 5 80K ATTORNEYS c. BOK 3,141,198 METHOD AND APPARATUS FOR HACKLING BAST FIBRE STALKS July 21, 1964 2 Sheets-Sheet 2 Filed Feb. 10, 1961 B mn m IILH/I, U I 3 L1. 5 /v 4- 8 |1| I 9 I 6 11m 1 I B I. F m M x n v W INVENTOR.

CORNELIS BOK BY ATTOR NEYS United States Patent 3,141,198 METHOD AND APPARATUS FOR HACKLING EAST FIBRE STALKS Cornelis Bok, Delft, Netherlands, assignor to N. V. Novivlas, Delft, Netherlands, a corporation of the Netherlands Filed Feb. 10, 1961, Ser. No. 88,448 Claims priority, application Netherlands Feb. 12, 1960 12 Claims. (CI. 19-13) The invention relates to a method and apparatus for hackling bast fibre stalks, whereby said stalks, clamped fast and with one end hanging down free, are guided through two or more hackling fields which are continuously moving in a vertical direction, and after having left a section of said hackling fields are carried to the next one, while having their other ends hanging down free.

Such a method is known and is, for instance, largely applied in the flax-using industries, in which it forms part of the so-called de-wooding of the stalks.

This de-wooding at the same time comprises the breaking whereby the woody parts are loosened from the fibres by breaking and stripping, and further the swingling, whereby part of said loosened woody parts are beaten from the fibre mass.

After these treatments then follows the hackling, whereby combs or pin-fields of varying density are drawn through the fibre mass. Hereby a cleaning effect is obtained, which at the same time loosens the fibres from one another and smoothes them so as to lie parallel.

In order to be able to withstand the pulling power of the pins the fibre material is generally gathered into so-called handfuls which are clamped fast.

Said handfuls run through the first hackling section whereby one freely dangling end of each handful is hackled. It is observed that one hackling section comprises several hackling fields. Hereby a hackling field is understood to comprise such a part of a hackling section as wherein the dimensions and the disposition of the hackling pins are constant. After leaving the first hackling section the handfuls are often changed in such a manner that the other end as Well as the part that had been clamped fast before, come to hang free and can be led through the next hackling section.

This treatment can, if desired, be repeated several times. At the same time, the pins of each successive hackling section, or the pins within each hackling section itself, of the successive hackling fields, can gradually grow thinner and the spacing of the pins can grow denser. Hereby a better result of the method is obtained.

It has been found that, surprisingly, the effect of the known method can still be considerably heightened.

Hereby the invention is founded on the following insight.

As a result of the continued hackling the fibre mass is thinned out. In order to get a favourable hackling result, as even as possible a loading of the hackling fields, as also a certain density of the material to be hackled are required.

In consequence of the thinning out of the fibre mass during hackling, the density of this material is not constant over the successive hackling fields. At the same time, between the handfuls there are always parts of the hackling fields, where the pins are not in contact with the fibre mass.

As a result of these factors it was in a general way established that all hackling fields were always only partly engaged and that the effect of the treatment by the second and, if present, of the following hackling sections was proportionally small.

These unfavourable conditions do not occur in the 3,141,198 Patented July 21, 1964 method according to the present invention. This invention consists in that the stalks are led through the first hackling section in an even stream and while being clamped fast, said stream being subsequently densified and thus carried to the next hackling section.

Thanks to the even clamping of the stalks while being led through the first hackling section, all the pins of the field present in this section are turned to the best advantage.

By the densification of the stream of stalks a sufficient density of the material is obtained also for the following hackling sections. The densification can be carried out in various ways.

Thus it is conceivable to adjust the flow of the fibre mass through the next hackling section to a lower transport velocity than in the preceding hackling section. Hereby a congestion of the fibre material is then brought about, which results in the forming of a densified even stream.

Although said method seems very attractive, yet it has certain drawbacks. A result of this method is, namely, that the transport systems of the mass of stalks should be independent for each hackling section. Each transport system should, therefore, have its own driving mechanism. At the same time it appears to be desirable, with a view to the further working up of the hackled material on combing and roving machines, that the material should leave the hackling apparatus divided in portions. All of this may give rise to an expensive and complicated construction which is not easily operated.

According to the invention these complications can be obviated, if the stalks are guided through each of the successive hackling fields at an equal speed and if the densification is effected after their passage through the first hackling section, by gathering the mass of stalks into mutually equal separate portions.

Preferably, these portions are hereby according to the invention densified to about half to two-thirds of their original breadth.

The density thus obtained is then adjusted well to the changed structure of the mass of stalks and to the diminished transport of these.

It is observed that it is true that part of the pins of the second hackling section remain inactive all the time, but this drawback appears to sink into insignificance as compared with the advantage that one and the same transport system for the stalk mass can be used for all the successive hackling fields.

According to the invention, the release of the stalks and their re-clamping in another place, between their passing through two hackling sections, can be very suitably effected, if the stalks are released from their clamped position shortly before they are densified, are subsequent- 1y during densification shifted on towards the non-hackled stalk ends and are finally clamped fast again after being densified.

Besides to the above-described method, the present invention also relates to an apparatus for hackling flax stalks, comprising two or more hackling sections which can move continuously in a vertical direction, each section comprising a plurality of hackling fields and between the hackling sections a take-over mechanism, and also clampingand transport systems for guiding flax stalks through the hackling sections while clamped fast and having their ends hanging free alternately.

In a known embodiment of this apparatus each section comprises two endless belts which are run about horizontal axles. Said belts, the so-called hackling sheets, which are on their outside provided with pins, together form a vertical slit, the walls of which move downward.

The clampingand transport system moves the stalks,

Which from the top downwards hang free within the slit, in a horizontal direction through said slit.

Consequently, the pins of the endless belts strike into the mass of stalks from above and are drawn downwards throughout it.

In the known apparatus the clamping system always comprises clamps consisting of two blocks, whereby a handful of stalks can be clamped between each clamp. The take-over system in these known apparatus comprises a mechanism for the successive releasing of the clamps, the turning of the handfuls and their subsequent reclamping.

It has already been described how a system is preferred by which a continuous stream of stalks is guided through the first hackling section and is subsequently densified.

According to the invention this appears to be possible when using an apparatus in which at least the clamping system of the first hackling section forms a continuous clamp at the location of said hackling section and over its entire width, and in which the take-over mechanism comprises a system for densifying the stream of flax stalks proceeding from the first hackling section.

The densification of the stream of flax stalks can be effected by having the velocity of the transport system of the first hackling section gradually slow down in the take-over mechanism.

All systems, in which the continuous coherence of the mass of stalks remains intact, have the drawback that they result in a complicated hackling machine.

On the other hand, a simple construction becomes possible, if, according to the invention, the densifying system comprises a separator periodically thrusting into the mass of stalks supplied from the first hackling section to form equally sized bundles of said stalks, as well as compartments which can move along with the stalks and keep them separated. Said separator may be a pin or a knife performing a rectilinear periodical movement transversely to the mass of stalks.

The compartments, which may be trough-shaped can be mounted beside each other on an endless belt in such a manner, that each bundle of stalks separated by the separator is always carried along in a separate troughshaped compartment.

However, a simpler embodiment of the compartments is obtained if the densifying system is formed by an endless screw worm which will turn about its axis, and one end of which is executed as a separator and the axis of rotation of which runs in the moving direction of the clamping systems and is positioned sideways under their ath. P Hereby the screw worm is preferably executed in such a manner that it consists of a strip, bent over a cylindrical plane, which strip is fixed to a driving shaft which is coaxial to the cylindrical plane, by means of spacers.

By this arrangement, the bundles of stalks which are separated by the various windings of the strip, are supported on the shaft of the screw worm. As the screw Worm revolves, the trough-shaped compartment, which is formed by the shaft and two spaced convolutions of the strip thereon, and in which is a separated bundle, moves away from the separator.

The direction of rotation of the screw worm is chosen in such a way that the bundles of flax stalks remain straightened out by the shaft against which they are supported. In order to prevent the rotating shaft from being wrapped round by the stalks, said shaft is positioned in such a way and is given such a thickness that it is impossible for the stalk ends to make a complete winding about it.

The separator formed by the bent strip tapering into a point keeps separating portions of stalks.

However, the stalks which remain on the other side of the separator, are in danger of being caught by the free end of the rotating shaft.

In order to prevent this happening and at the same time to be also able to immediately support the separated portions, in an embodiment according to the present invention the screw worm is executed in such a way that it is shaftless at the end which is turned towards the separator, and that at that same place an axially disposed support for the stalks is present at about half the radius of the screw worm and lagging in phase with respect to the separator.

According to a simple embodiment the driving shaft of the screw worm hereby at its free end gives into a hollow, open cylindrical wall, the rim of which is shaped as a single saw-tooth, the axially disposed part of which provides the support lagging by from 50 to 60 in phase with respect to the separator.

This lagging in phase of the axially disposed support with respect to the separator has proved necessary, in order to prevent the support from stopping the separators being thrust into the mass of stalks.

According to the invention a densification of the mass of stalks favourable to the hackling process is obtained if the width of each trough-shaped compartment is about one half to two-thirds of the pitch of the screw-worm.

In the strip-shaped screw Worm this means that the breadth of the strip, measured in the direction of the shaft, is from about equal to to half the size of the free space between the successive strip windings.

In order to be able to form a continuous stream of stalks for entrance into the first hackling section, diverse clamping systems for the stalks can be conceived of.

For instance, a clamping system may be conceived, comprising a system of movable clamping blocks, which clamping blocks closely fit together and in this manner form one single clamp across the whole of the handling section.

A construction of the clamping system according to the present invention becomes considerably simpler and lighter. In this construction at least the clamping system of the first hackling section comprises two running belts disposed over one another, said belts lying against each other over the length of said hackling section. These running belts meet each other at the beginning of the hackling section and move away from each other again when leaving the hackling section.

At the place where the belts touch each other, the stalks are continuously supplied with their lengths directed transversely to the belts.

In this manner the stalks remain clamped in continuous formation over the entire length of the hackling field.

With a view to supporting the belts, they are according to the invention made to fit into U-shaped links over the entire length of the hackling section, said links forming part of a link chain circulating over said hackling section, over two reversing discs situated in a vertical plane.

A considerable simplification of the hackling apparatus now becomes possible in an embodiment, which is such that the clamping systems of the successive hackling sections are analogous, that'the running belts are common and that the upper belt is between the sections lifted from the lower belt by diverting device.

By the lifting up of the upper band by the diverting device the clamping of the stalks between both belts is discontinued, which makes it possible for the stalks to be separated into portions. After this separation the belts join again and the stalks are clamped fast again as portions. In this arrangement they are subsequently supplied to the next hackling section.

The lower belt has to carry the weight of the upper belt as well as of the mass of stalks.

Of the upper belt it is required that it be flexible enough to be bent over the diverting device.

Lastly, at least one of the belts should consist of a material sufficiently clinging to prevent the stalks from being pulled from between the belts under the influence in of the action of the forces which are brought to bear on them in the hackling fields.

According to the present invention it has proved useful if to this end the lower running belt is a thick rubber belt and the other running belt is a leather belt.

In the hackling apparatus we assumed as known the handfuls of stalks are, each time they have passed a hackling section, taken from the clamps, reversed and put to again.

While this is being effected, the hanging part of the stalks always remains on the same side of the clamps, and, therefore, the mutual positioning of the hackling sections does not present any difliculties.

Said hackling sections can namely be arranged after one another in one single plane.

However, in the apparatus according to the invention the situation is different. As a matter of fact in said apparatus the free hanging stalk ends are hung on a different side of the clamping system in each successive hackling section.

Now, if the clamping systems of the successive hackling sections should lie in one line, one behind the other, the hackling sections would turn and turn about have to be shifted in transverse direction with respect to each other, in order that the stalk ends hanging from the clamping systems would hang in the hackling fields in a truly vertical position.

Now such an arrangement of the hackling apparatus brings about a considerable complication, as then the various hackling fields cannot be driven by common shafts.

According to the invention it is possible to avoid this complication, if the paths of the clamping systems of two successive hackling sections have with respect to each other been shifted sideways over the breadth of a clamping, in such a Way, that the free hanging stalk ends of all the hackling fields lie in one single plane.

The re-arranging of the stalks between the successive hackling sections can be effected by hand. It is namely conceivable for the stalks, after they have been bundled but not yet reclamped, to be drawn through by hand one by one in a transverse direction. This is tedious work, which, especially if the producing velocity is increased, is found to set a limitation to the tempo. At the same time the accuracy of the drawing through of the bundles decreases at higher transport velocities.

Now according to the invention it has been found possible to construct the take-over mechanism between the hackling sections in such a manner that it comprises an additional conveying system, which, between the hackling sections, shifts the stalks in a transverse direction in the direction of the stalk ends not hanging free in the preceding hackling section.

According to the invention it is preferred for the apparatus to besuch that the additional transport system of the take-over mechanism and the screw worm are situated on either side of the clampingand conveying system for the stalks and that said transport system and said screw-worm they can be driven during operation by oppositely directed components of motion.

Hereby it has been found that by this arrangement the separation of the mass of stalks into bundles progresses more satisfactorily.

According to the preferred embodiment of the invention, said additional transport system comprises a circulating string, which in one part of its course runs through a smooth trench, all of this in such a manner that the string and the trench approach each other on either side of the stalk ends not hanging free in the preceding hackling field.

Surprisingly it has been found that, if the string is made of a sufiiciently clinging material, for instance of rubber, it is possible to clamp the stalks between the string and the smooth trench and at the same time to have them conveyed along with the string.

That part of the strings course in which it runs through the smooth trench, is situated in a horizontal plane and gradually deviates from the direction in which the main transport of the stalks takes place. The stalks clamped in between the string and the trench are thus drawn through in transverse direction over a determined distance.

This takes place simultaneously with the separation of the stalks into portions and with the release of the stalks from the clamping system of the preceding hackling field.

Lastly, the invention relates to the fibre material obtained by hackling according to one of the hereinbefore described methods or with one of the above-described apparatus.

Said fibre material shows a particularly favourable evenness and has been most intensively cleaned of its undesired parts.

With the aid of a few figures, a partly schematical description of an embodiment of an apparatus according to the invention will now be given in order to make the invention more clear.

FIGURE 1 is a schematical front view, in which the foremost hackling sheet has been removed.

FIGURE 2 and FIGURE 3 show transv-ersional crosssections along II-II and III-III in FIGURE 1 respectively.

FIGURE 4 is a top view of a passing-on mechanism between two successive hackling sections.

FIGURE 5 and FIGURE 6 are a transversional crosssectional and a front view respectively of parts of said passing-on mechanism. At the same time FIGURE 5 is a transversional cross-section along V-V in FIGURE 6 whereby some elements above in FIGURE 6 have been omitted from FIGURE 5 for the sake of clarity.

In the FIGURES 1, 2 and 3 the reference numerals 1 and 2 respectively indicate pairs of hackling sheets. Hereby each pair of hackling sheets forms a hackling section, which in itself comprises a plurality of hackling fields. The hackling sheets 1 form the first hackling section, the sheets 2 the second.

The endless sheets can be moved pairwise in the directions indicated by arrows by a driving system which is not shown, in such a manner, that they form a slit having walls that move downwards.

At the lower side, the hackling sheets are reversed over the drums 3 and 4 respectively and at the upper side over the rollers 5 and 6 respectively.

The hackling sheets 1 and 2 are provided with hackling pins 7. Substantially over the slits formed by the belts 1 and 2 the running belts 8 and 9 are disposed so as to be movable in the direction of the arrows.

Belt 8 is a thick rubber belt and belt 9 is a leather belt. Said belts 8 and 9 can be driven by a driving mechanism which is not drawn.

Between the rubber belt 8 and the belt 9, a continuous stream of stalks 10 is supplied at the beginning of the first hackling field, where said belt 8 and said belt 9 are made to join each other in a manner, not shown, but known in the art.

In this way said stalks 10 are clamped between the belts 8 and 9 transversely to the direction of said belts.

Wherever the belts 8 and 9 continue to run after having been pressed together, this clamping of the stalks 10 also continues, which is along the entire lengths of the hackling sections.

Between the hackling sections the leather belt 9 is guided over the device 11, whereby the stalks 10 are released from clamping.

In the first hackling section the clamping of the stalks 10 is such that more than one half of the lengths of said stalks protrudes towards the front and hangs down free in the slit between the hackling sheets 1.

The other ends of the stalks glide over the trench 12.

At the location of the second hackling section more than half of the lengths of the stalks hang free in the slit between the hack-ling sheets at the back of the belts 8 and 9. The front ends of the stalks 10 which had been hackled before then glide over the trench 13.

The reversing wheels 14 and 15 are used to revert two link chains 16 and 17 in the directions indicated by the arrows.

Said link chains are constructed out of the links 18 (see FIGURES 5 and 6), which are hingingly coupled to one another.

The links 18 are U-shaped, in such a manner that the link chains 16 and 17 form a trench, in which the rubber belt 8 and the leather belt 9 are supported and by which they are carried along.

Through the second hackling section the stalks ltl run in bundles.

Therefore in the region where the leather belt is lifted by the diverting device 11, the stalks must be passed on in transverse direction and further gathered into bundles.

At the same time the stalk ends, which at first glided in the trench 12, should now hang down free and those ends, which hung down free at first should now be led into the trench 13.

To this end several provisions are made, which are further indicated in the FIGURES 4, 5 and 6.

On the frame of the apparatus a revolving shaft 19 is rotatably fixed in the bearing 20 (FIGURE 6).

Said revolving shaft 19 runs parallel to the path of the belt 8 through the hackling fields before and under said path (FIGURE 5).

By means of a pulley 21 and a belt 22 the shaft can be driven in the direction indicated by the arrow (FIG- URE 6).

With the said of the coupling means 23 the hollow cylinder mantle 24 is fixed to the revolving shaft 19, so that the mantle can follow the revolving movement of the shaft -19 (FIGURES 5 and 6).

A strip 25 is in turn coupled to said mantle 24 by the spacers 26. Said strip 25, which is bent in the form of a screw thread, at the left side tapers into a point 27 (FIG- URES 4 to 6).

The left end edge of the cylindre mantle 24 is shaped like a saw-tooth, i.e., the edge has the shape of a single convolution of a helix, the ends of which are connected by an axially running straight part.

The straight part 28 of said saw-tooth, running in axial direction, extends from the left end of the strip over a little more than one entire winding and thereby lags in phase by 55 with respect to the point 27 (FIGURES 4 and 6).

The point 27 serves as separator. At each revolution namely it thrusts through the continuous stream coming from the first hackling section and separates a bundle from it. Said bundle is pushed forward by the supporting rim 28, the stalks of said bundle remaining supported on the cylindre mantle 24 when the screw worm continues to turn on.

The velocity of the belt 8, the pitch and the number of turns of the screw worm are correspondingly selected to be of such values that the bundle of stalks is conveyed to the right by the screw worm at the velocity of the belt 8.

The separation into bundles of the stalks 10 can continue as far as past the belts 8 and 9, as the latter no longer clamp the stalks.

The stalk ends hanging free over the cylindre mantle should glide through the trench 13 when in the second hackling section (FIGURE 3).

To this end the carrier plate 29 to the right of the screw worm extends into the cylindre mantle 24, which carrier plate 29 is connected with the trench 13 by means of the stower plate 30 (FIGURES 4 and 6).

The shapes of the parts 29 and 30 are such that the stalks 10 being pressed to the right side of the cylindre mantle 24 by the strip 25, are automatically guided into the trench 13 (FIGURE 4).

In the same manner the plates 31 and 32 are connected to the trench 12. The passer-on plate 31 runs obliquely forwards and downward from the trench 12. In this manner the stalk ends, which at first glided along in the trench 12, now fall down free.

In the same manner, however, the stalk ends, which were hanging down free in the first hackling section, are now lifted forward. From the passer-on plate 31 these latter stalk ends slide on to the supporting plate 32, which supports them as a curtain hanging obliquely forward, as far as into the screw worm.

In this way the separator 27 can at every upward movement separate a bundle from off this curtain of stalks, which bundle can subsequently be conveyed forwards by the supporting rim 28 and to the right by the strip 25.

It is observed that an embodiment is possible, in which the supporting plate 32 carries a bearing at its right end for supporting the screw worm.

An additional stower plate 33 takes care of an even distribution of the stalk ends on the passer-on plate 31 (FIGURE 4).

Attention is drawn to the fact that the paths of the rubber belt 8 and of the leather belt 9 between the two hackling sections runs obliquely forward, and that over a distance which approximately corresponds to the breadth of said belts 8 and 9 (FIGURES 2 and 3).

Hereby it is achieved that the hanging stalk ends form one single plane throughout the successive hackling fields.

As a result hereof, the shafts of the drums 3 and 4 on the one side, and of the rollers 5 and 6 on the other side of the two hackling sections are in direct line with one another.

A trench 34 and a string 35 take care of the drawing through of the stalks between the rubber belt 8 and the leather belt 9, at the location where these are separated from each other (FIGURE 4).

The trench 34 begins at the left side of wheel 14 under the rubber belt 8 and subsequently deviates away from the direction in which the main transport of the stalks takes place between the hackling sections and curves in a horizontal plane toward the direction in which the transverse shifting of the stalks is accomplished.

Said trench 34 has a U-shaped cross-section, which opens towards the back of the apparatus as shown in FIG. 4, i.e., the opening faces in the direction in which the transverse shifting of the stalks takes place. It is made of a smooth material having a smooth finish.

The string 35 runs through that part of the trench 34 which trends backwards.

Said string is guided over the rollers 36, 37 and 38. The roller 38 at the same time takes care of the driving of the string 35 in the direction indicated by the arrow.

In contrast to the trench 34, the string is made of a clinging material, for instance rubber.

The stalk ends falling from the trench 12 are caught and clamped between the trench 34 and the string 35.

As the trench 34 is smooth and the string 35 has a better grip, the stalk material will be dragged along by the string 35, without slipping through the trench in transverse direction.

Hereby the string 35 draws the stalks through between the rubber belt 8 and the leather belt 9.

The speed of the string 35 is almost completely adjusted to the speed of the belts 8 and 9.

The trench 34 ends at an ample distance before the guiding roller 38. Here, the clamped stalk ends are then released and fall down.

In this way it is impossible for the stalks to get entangled in the roller 38.

After the stalks 10 have thus been drawn through and separated into bundles, the belts 8 and 9 join each other again and clamp the stalks between them.

It can be seen from the above detailed description that the novel hackling apparatus of the instant invention functions as follows: A mass of bast fibre stalks is fed between the belts 8 and 9 so that they are clamped with more than one-half of the stalks hanging down between the first of a series of hackling sections such as that indicated by reference numeral 1 shown in FIGURE 1. The continuously moving clamping belts 8 and 9, driven by belt 16, composed of hingedly coupled U-shaped links 18, transport the stalks from the first hackling field to the vicinity of the screw-worm, where the belts are separated by the diverter 11 (FIGURE 6). At this point, the unhackled stalk ends are picked up and shifted in a transverse direction by the belt 35 and the trench 34. While the stalks are so held, the separator 27 acts to separate the hackled ends of the stalks into separate and discrete bundles which are transported by the individual compartments between the windings of the helix of the screw-worm. The stalk ends are then dropped from between the belt 35 and the trench 34 at a point where the belts 8 and 9 again converge, and the now densified bundles of stalks are reclamped at the previously hackled stalk ends by the belts and are fed by the clamping belts to the next succeeding hackling section.

It has been found that with the above-described hackling apparatus a larger output can be achieved, by which the fibres of the stalk material have been loosened from each other and have been laid parallel in a better way and have been more thoroughly cleaned of impurities.

It is observed that diverse smaller variations to this embodiment are possible, especially with regard to the shape and the dimensions of the screw worm and the various trenches and supporting plates.

At the same time it is thinkable, that the separator should be conceived of as loose from the screw worm, or that the drawing-through mechanism formed by the trench 34 and the string 35 should be constructed in a different manner.

All of these as well as other variations are considered as falling under the present invention.

What is claimed is:

1. A method for hackling bast fibre stalks which comprises clamping a mass of said stalks to allow one end of said stalks to hang freely, passing said hanging ends of said clamped stalks through a vertical hackling field to contact the hackling elements of said hackling field, releasing the clamped ends of said stalks after the passage thereof through said first hackling field, collecting said unclamped stalks into a mass of greater density than that passed through said first hackling field, clamping said densified stalks at the previously hackled ends of said stalks to allow the unhackled ends thereof to hang freely, and passing said unhackled ends of said densified stalks through a second vertical hackling field to contact the hackling elements thereof.

2. The method according to claim 1, wherein said stalks are passed through said first and second hackling fields at substantially the same speed, and said densification is effected by gathering portions of said unclamped mass of stalks into substantially equal-sized bundles.

3. The method according to claim 2, wherein the width of said densified bundles is in the range of from about 12 to about /3 of the initial width of said gathered portions of said unclamped, undensified mass of stalks.

4. An apparatus for hackling bast fibre stalks which comprises two separate vertical hackling sections which are horizontally aligned in essentially a common plane, each of said hackling sections having a pair of endless rotatable sheets provided with a plurality of hackling elements, said sheets in each of said hackling sections being spaced sufficiently close that said hackling elements on both of said sheets contact fibre stalks passed between said pair of sheets, a continuous clamping and transporting means for said stalks which is operable over the entire width of each of said hackling sections, said clamping means being adapted to clamp one end of said stalks to allow the other end of said stalks to hang freely between said sheets of said hackling sections, means for unclamping said stalks from said hackling section clamping and transporting means after the passage of said stalks through the first of said hackling sections, and means operable with said hackling section clamping and transporting means for transporting said unclamped stalks between said two separate hackling sections, said means for transporting said unclamped stalks between said two separate hackling sections including means for shifting said unclamped stalks transversely to bring the ends of said stalks which were unclamped during the passage of said stalks through the first of said hackling sections into alignment with said hackling section clamping and transporting means so that said stalks are reclamped by said hackling section clamping and transporting means at the previously hackled ends of said stalks for passage through the second of said two hackling sections, and said means for transporting said unclamped stalks between said two separate hackling sections further including means to gather said unclamped stalks between said two separate hackling sections into a plurality of separate densified bundles of stalks, each of which bundles having a density greater than that of the mass of stalks passed through the first of said hackling sections and to maintain said densified bundles separate from one another until clamped in that form by said hackling section clamping and transporting means for passage through said second hackling section.

5. An apparatus according to claim 4, wherein said hackling section clamping and transporting means comprises two endless rotatable belts, said belts being adapted to be in engagement with each other over the entire width of each of said first and second hackling sections.

6. The apparatus according to claim 5, wherein said means for unclamping said stalks from said hackling section clamping and transporting means comprises means for diverting said belts from engagement in the region between said two hackling sections.

7. The apparatus according to claim 5, wherein one of said belt pair is formed of leather and the other of said belts is formed of rubber.

8. The apparatus according to claim 4, wherein said hackling section clamping and transporting means in the region of said second hackling section is shifted transversely with respect to the path thereof in the region of said first hackling section by a distance which is substantially equal to the breadth of said clmping and transporting means so that the unclamped ends of said stalks pass through said first and second hackling sections in substantially a common plane.

9. The apparatus according to claim 4, wherein said gathering means comprises a rotatable screw-worm consisting of a helical strip positioned in a cylindrical plane around and fixedly attached to a rotatable shaft which is co-axial to said cylindrical plane, said shaft: being parallel to the direction of travel of said unclamped stalks between said two hackling sections and said shaft being spaced laterally from and vertically below the plane of travel of said unclamped stalk transport means between said two hackling sections, the end of said helical strip toward said first hackling section being unattached and tapered to define a point, said shaft being supported only at the end toward said second hackling section and said shaft being partially cut away at the unsupported end thereof to form an axially disposed support for said unclamped stalks over about /2 the radius of said screwworm in the region of said point of said helical strip, said axially disposed support lagging in phase with respect to said point of said helical strip, and the slanted windings of said helical strip and said shaft forming: a plurality of separate trough-shape compartments movable by the rotation of said screw-worm in the direction of travel of said unclamped stalks between said two hackling sections.

10. The apparatus according to claim 9, wherein the Width of said trough-shaped compartments is about /2 to about of the pitch of said helical strip.

11. The apparatus according to claim 9, wherein the leading edge of said axially disposed support during rotation of said screw-worm lags in phase from about 50 to about 60 with respect to said point of said helical strip.

12. The apparatus according to claim 4, wherein said means for effecting said transverse shifting and said transporting of said unclamped stalks between said two separate hackling sections comprises a curved member having a U-shaped cross-section which member is located between said first and second hackling sections, the opening of said U-shaped cross-section of said curved member facing in the direction of said transverse shifting of said stalks, said curved member being curved in said direction of stalk transverse shifting along the path of said curved member toward said second hackling section to define a plane and said curved member being positioned so that the direction of travel of said unclamped stalks between said hackling sections lies in said plane defined by said curved member, an endless rotatable string which is internally slidably engageable with said curved member over a portion of the path of said curved member between said first and second hackling sections, said string being formed of a material which is frictionably engageable with said stalks, and means for rotatably driving said endless string so that in the region of contact with said curved member said string runs in the direction of travel of said unclamped stalks between said hackling sections, the engagement of said string and said curved member being such that stalk ends clamped in said first hackling section are engaged between said string and said curved member substantially simultaneously with the operation of said unclamping means and stalks engaged between said string and said curved member are released for passage through said second hackling section at a point coinciding with a reclamping operation of said hackling section clamping and transporting means.

References Cited in the file of this patent UNITED STATES PATENTS 1,258,571 Humphrys Mar. 5, 1918 1,313,841 Summers Aug, 19, 1919 FOREIGN PATENTS 216,127 Great Britain Aug. 6, 1925 

4. AN APPARATUS FOR HACKLING BAST FIBRE STALKS WHICH COMPRISES TWO SEPARATE VERTICAL HACKLING SECTIONS WHICH ARE HORIZONTALLY ALIGNED IN ESSENTIALLY A COMMON PLANE, EACH OF SAID HACKLING SECTIONS HAVING A PAIR OF ENDLESS ROTATABLE SHEETS PROVIDED WITH A PLURALITY OF HACKLING ELEMENTS, SAID SHEETS IN EACH OF SAID HACKLING SECTIONS BEING SPACED SUFFICIENTLY CLOSE THAT SAID HACKLING ELEMENTS ON BOTH OF SAID SHEETS CONTACT FIBRE STALKS PASSED BETWEEN SAID PAIR OF SHEETS, A CONTINUOUS CLAMPING AND TRANSPORTING MEANS FOR SAID STALKS WHICH IS OPERABLE OVER THE ENTIRE WIDTH OF EACH OF SAID HACKLING SECTIONS, SAID CLAMPING MEANS BEING ADAPTED TO CLAMP ONE END OF SAID STALKS TO ALLOW THE OTHER END OF SAID STALKS TO HANG FREELY BETWEEN SAID SHEETS OF SAID HACKLING SECTIONS, MEANS FOR UNCLAMPING SAID STALKS FROM SAID HACKLING SECTION CLAMPING AND TRANSPORTING MEANS AFTER THE PASSAGE OF SAID STALKS THROUGH THE FIRST OF SAID HACKLING SECTIONS, AND MEANS OPERABLE WITH SAID HACKLING SECTION CLAMPING AND TRANSPORTING MEANS FOR TRANSPORTING SAID UNCLAMPED STALKS BETWEEN SAID TWO SEPARATE HACKLING SECTIONS, SAID MEANS FOR TRANSPORTING SAID UNCLAMPED STALKS BETWEEN SAID TWO SEPARATE HACKLING SECTIONS INCLUDING MEANS FOR SHIFTING SAID UNCLAMPED STALKS TRANSVERSELY TO BRING THE ENDS OF SAID STALKS WHICH WERE UNCLAMPED DURING THE PASSAGE OF SAID STALKS THROUGH THE FIRST OF SAID HACKLING SECTIONS INTO ALIGNMENT WITH SAID HACKLING SECTION CLAMPING AND TRANSPORTING MEANS SO THAT SAID STALKS ARE RECLAMPED BY SAID HACKLING SECTION CLAMPING AND TRANSPORTING MEANS AT THE PREVIOUSLY HACKLED ENDS OF SAID STALKS FOR PASSAGE THROUGH THE SECOND OF SAID TWO HACKLING SECTIONS, AND SAID MEANS FOR TRANSPORTING SAID UNCLAMPED STALKS BETWEEN SAID TWO SEPARATE HACKLING SECTIONS FURTHER INCLUDING MEANS TO GATHER SAID UNCLAMPED STALKS BETWEEN SAID TWO SEPARATE HACKLING SECTIONS INTO A PLURALITY OF SEPARATE DENSIFIED BUNDLES OF STALKS, EACH OF WHICH BUNDLES HAVING A DENSITY GREATER THAN THAT OF THE MASS OF STALKS PASSED THROUGH THE FIRST OF SAID HACKLING SECTIONS AND TO MAINTAIN SAID DENSIFIED BUNDLES SEPARATE FROM ONE ANOTHER UNTIL CLAMPED IN THAT FORM BY SAID HACKLING SECTION CLAMPING AND TRANSPORTING MEANS FOR PASSAGE THROUGH SAID SECOND HACKLING SECTION. 